compile templates only once on app start instead of on every page request

main.go

@@ -3,8 +3,10 @@ package main
 import (
 	"flag"
 	"fmt"
+	"html/template"
 	"log"
 	"net/http"
+	"path/filepath"
 
 	"git.icyphox.sh/legit/config"
 	"git.icyphox.sh/legit/routes"
@@ -29,7 +31,10 @@ func main() {
 		log.Fatalf("unveil: %s", err)
 	}
 	
-	mux := routes.Handlers(c)
+	tpath := filepath.Join(c.Dirs.Templates, "*")
+	t := template.Must(template.ParseGlob(tpath))
+
+	mux := routes.Handlers(c, t)
 	addr := fmt.Sprintf("%s:%d", c.Server.Host, c.Server.Port)
 	log.Println("starting server on", addr)
 	log.Fatal(http.ListenAndServe(addr, mux))

routes/handler.go

@@ -2,6 +2,7 @@ package routes
 
 import (
 	"net/http"
+	"html/template"
 
 	"git.icyphox.sh/legit/config"
 	"github.com/alexedwards/flow"
@@ -29,9 +30,9 @@ func (d *deps) Multiplex(w http.ResponseWriter, r *http.Request) {
 	}
 }
 
-func Handlers(c *config.Config) *flow.Mux {
+func Handlers(c *config.Config, t *template.Template) *flow.Mux {
 	mux := flow.New()
-	d := deps{c}
+	d := deps{c, t}
 
 	mux.NotFound = http.HandlerFunc(func(w http.ResponseWriter, _ *http.Request) {
 		d.Write404(w)

routes/routes.go

@@ -21,6 +21,7 @@ import (
 
 type deps struct {
 	c *config.Config
+	t *template.Template
 }
 
 func (d *deps) Index(w http.ResponseWriter, r *http.Request) {
@@ -70,14 +71,11 @@ func (d *deps) Index(w http.ResponseWriter, r *http.Request) {
 		return infos[j].d.Before(infos[i].d)
 	})
 
-	tpath := filepath.Join(d.c.Dirs.Templates, "*")
-	t := template.Must(template.ParseGlob(tpath))
-
 	data := make(map[string]interface{})
 	data["meta"] = d.c.Meta
 	data["info"] = infos
 
-	if err := t.ExecuteTemplate(w, "index", data); err != nil {
+	if err := d.t.ExecuteTemplate(w, "index", data); err != nil {
 		log.Println(err)
 		return
 	}
@@ -138,9 +136,6 @@ func (d *deps) RepoIndex(w http.ResponseWriter, r *http.Request) {
 		log.Printf("no readme found for %s", name)
 	}
 
-	tpath := filepath.Join(d.c.Dirs.Templates, "*")
-	t := template.Must(template.ParseGlob(tpath))
-
 	if len(commits) >= 3 {
 		commits = commits[:3]
 	}
@@ -154,7 +149,7 @@ func (d *deps) RepoIndex(w http.ResponseWriter, r *http.Request) {
 	data["servername"] = d.c.Server.Name
 	data["gomod"] = isGoModule(gr)
 
-	if err := t.ExecuteTemplate(w, "repo", data); err != nil {
+	if err := d.t.ExecuteTemplate(w, "repo", data); err != nil {
 		log.Println(err)
 		return
 	}
@@ -247,9 +242,6 @@ func (d *deps) Log(w http.ResponseWriter, r *http.Request) {
 		return
 	}
 
-	tpath := filepath.Join(d.c.Dirs.Templates, "*")
-	t := template.Must(template.ParseGlob(tpath))
-
 	data := make(map[string]interface{})
 	data["commits"] = commits
 	data["meta"] = d.c.Meta
@@ -258,7 +250,7 @@ func (d *deps) Log(w http.ResponseWriter, r *http.Request) {
 	data["desc"] = getDescription(path)
 	data["dotdot"] = filepath.Dir(path)
 
-	if err := t.ExecuteTemplate(w, "log", data); err != nil {
+	if err := d.t.ExecuteTemplate(w, "log", data); err != nil {
 		log.Println(err)
 		return
 	}
@@ -286,9 +278,6 @@ func (d *deps) Diff(w http.ResponseWriter, r *http.Request) {
 		return
 	}
 
-	tpath := filepath.Join(d.c.Dirs.Templates, "*")
-	t := template.Must(template.ParseGlob(tpath))
-
 	data := make(map[string]interface{})
 
 	data["commit"] = diff.Commit
@@ -299,7 +288,7 @@ func (d *deps) Diff(w http.ResponseWriter, r *http.Request) {
 	data["ref"] = ref
 	data["desc"] = getDescription(path)
 
-	if err := t.ExecuteTemplate(w, "commit", data); err != nil {
+	if err := d.t.ExecuteTemplate(w, "commit", data); err != nil {
 		log.Println(err)
 		return
 	}
@@ -332,9 +321,6 @@ func (d *deps) Refs(w http.ResponseWriter, r *http.Request) {
 		return
 	}
 
-	tpath := filepath.Join(d.c.Dirs.Templates, "*")
-	t := template.Must(template.ParseGlob(tpath))
-
 	data := make(map[string]interface{})
 
 	data["meta"] = d.c.Meta
@@ -343,7 +329,7 @@ func (d *deps) Refs(w http.ResponseWriter, r *http.Request) {
 	data["tags"] = tags
 	data["desc"] = getDescription(path)
 
-	if err := t.ExecuteTemplate(w, "refs", data); err != nil {
+	if err := d.t.ExecuteTemplate(w, "refs", data); err != nil {
 		log.Println(err)
 		return
 	}

routes/template.go

@@ -2,42 +2,33 @@ package routes
 
 import (
 	"bytes"
-	"html/template"
 	"io"
 	"log"
 	"net/http"
-	"path/filepath"
 	"strings"
 
 	"git.icyphox.sh/legit/git"
 )
 
 func (d *deps) Write404(w http.ResponseWriter) {
-	tpath := filepath.Join(d.c.Dirs.Templates, "*")
-	t := template.Must(template.ParseGlob(tpath))
 	w.WriteHeader(404)
-	if err := t.ExecuteTemplate(w, "404", nil); err != nil {
+	if err := d.t.ExecuteTemplate(w, "404", nil); err != nil {
 		log.Printf("404 template: %s", err)
 	}
 }
 
 func (d *deps) Write500(w http.ResponseWriter) {
-	tpath := filepath.Join(d.c.Dirs.Templates, "*")
-	t := template.Must(template.ParseGlob(tpath))
 	w.WriteHeader(500)
-	if err := t.ExecuteTemplate(w, "500", nil); err != nil {
+	if err := d.t.ExecuteTemplate(w, "500", nil); err != nil {
 		log.Printf("500 template: %s", err)
 	}
 }
 
 func (d *deps) listFiles(files []git.NiceTree, data map[string]any, w http.ResponseWriter) {
-	tpath := filepath.Join(d.c.Dirs.Templates, "*")
-	t := template.Must(template.ParseGlob(tpath))
-
 	data["files"] = files
 	data["meta"] = d.c.Meta
 
-	if err := t.ExecuteTemplate(w, "tree", data); err != nil {
+	if err := d.t.ExecuteTemplate(w, "tree", data); err != nil {
 		log.Println(err)
 		return
 	}
@@ -70,9 +61,6 @@ func countLines(r io.Reader) (int, error) {
 }
 
 func (d *deps) showFile(content string, data map[string]any, w http.ResponseWriter) {
-	tpath := filepath.Join(d.c.Dirs.Templates, "*")
-	t := template.Must(template.ParseGlob(tpath))
-
 	lc, err := countLines(strings.NewReader(content))
 	if err != nil {
 		// Non-fatal, we'll just skip showing line numbers in the template.
@@ -90,7 +78,7 @@ func (d *deps) showFile(content string, data map[string]any, w http.ResponseWrit
 	data["content"] = content
 	data["meta"] = d.c.Meta
 
-	if err := t.ExecuteTemplate(w, "file", data); err != nil {
+	if err := d.t.ExecuteTemplate(w, "file", data); err != nil {
 		log.Println(err)
 		return
 	}